Machine for slitting sheets of metal, paper, or other fabrics.



No. 782,977. PATENTED 'FEB. 21, 1905. A. F. MADDEN.

MACHINE POE SLITTING SHEETS 0F METAL, PAPER, OR OTHER FABRICS.

APPLICATION FILED 001219, 1904.

5y; munmummum\nm\\\nnmm\m l MW \HHWHHHHHIHUHH\HHHHIHIHHHHHH mm m UIWHHHWHHHHWWHHHHHHHHWW1 NW Patented February 21, 1905.

ALBERT F. MADDEN, OF NEWVARK, NET/V JERSEY.

MACHINE FOR SLITTING SHEETS 0F METAL, PAPER, OR OTHER FABRICS.

SPECIFICATION forming part of Letters Patent No. 782,977, dated February21, 1905. Application filed October 19, 1904. Serial No- 229,106.

To a 1072 0717, it may concern:

Be it known that I, ALBERT F. MADDEN, a citizen of the United States,residing at Newark, in the county of Essex and State of New Jersey, haveinvented certain new and useful Improvements in Machines for SlittingSheets of Metal, Paper, or other Fabrics, of which the following is aspecification, reference being had to the drawings accompanying andforming part of the same.

My invention relates to machines for cutting slits in sheet metal,paper, rubber, cloth, and other materials, and has for its object toprovide such an apparatus by which a sheet of material may be slittedwith the utmost accuracy as to the uniformity of the spaces between theslits.

A further object is to provide slit-cutters of a character which can beeasily and cheaply constructed in such a way as to perform theirfunctions with the desired degree of accuracy and which also can beeasily sharpened without in any way impairing their accuracy ofoperation. p

A further object of the invention is toprovide a machine of the simplestpossible character, though the invention may of course be embodied inmore complicated forms than that herein specifically shown anddescribed, if desired.

In practicing my invention I make use of two coacting cutters upon whichare formed shear edges, which cooperate as right and left handedscrew-threads. In the preferred embodiment I take two rolls or cylindersof suitable size and upon one form a right-hand thread and upon theother a left-hand thread. The cutters so made are mounted with theirthreads in shearing contact, with the result that if the rollers arerevolved and a sheet of material introduced between them it will be cutin slits, the number of which will depend upon the number of threads onthe cutters and the distance between the slits upon the pitch of thesaid threads. As these characteristics may be varied almostindefinitely, it will be seen that there is practically no limit to thevariety of the work which my invention can perform in slitting all kindsof material. By stopping out the threads on one or both outters, as bycutting one or more longitudinal grooves in the same, which of coursewill operateto omit the cutting effect for a space equal to the width ofthe groove, the slits will be produced in parallel rows. If the threadsare stopped out in staggered relation to each other,

the slits will also be staggered. In this way a great variety of effectsmay be produced, as will appear more fully hereinafter.

The accompanying drawings show a convenient and simple embodiment of myinvention, and, referring thereto for a more complete explanation of thesame, Figure 1 shows the apparatus in front elevation. Fig. 2 is adetail view showing the shearing engagement of the threads on the tworollers. Fig. 3 is a detail view showing rollers having longitudinalgrooves interrupting the cutting-threads. Fig. 4, is a detail viewshowing rollers for producing staggered slits. Figs. 5 and 6 showportions of sheets cut by the rollers of Figs. 3 and 4, respectively.

The slitting-rollers, preferably of equal size, are indicated by thenumerals 1 and 2, respectively, one having a right-hand thread and theother a left-hand thread. The two are mounted in suitable bearings withthe threads in shearing contact with each other, as shown in Fig. 2, andare provided with any convenient mechanism for rotating them upon eachother. In such rotation the shearing engagement of the threads with eachother will always be preserved by reason of the opposite inclination ofthe threads, so that a sheet of material introduced between the samewill be cut from end to end and as many slits formed as there arethreads on the rollers. The spaces between the slits depend, as beforestated, upon the pitch of the threadsthat is, the distance of thethreads apart. If the rollers are separated so that the threads are notactually in contact, the cut will of course not extend entirely throughthe sheet of material, but will produce parallel grooves of greater orless depth, depending on the thickness of the sheet, the distancebetween the rollers, and the depth of the threads, as will be readilyunderstood. \Vhen the cut is to extend clear through the sheet, thedepth of the threads must be to a certain extent regulated by thethickness of the material, a very thick sheet requiring deeper threadsthan a very thin one. Within easily determined limits sheets of variousthicknesses may be cut with the same rollers. rollers may be mounted inbearings which will permit longitudinal adjustment thereof, so that theshearing engagement of the two threads may be varied. Any convenientmeans may be employed for this purposcas, for example, the screw 3bearing against the shaft of the lower roller, so that it maybe shiftedto bring its threads into as close contact with the threads on the otheras desired.

It will be noted that the slits produced by the device are not at rightangles to the axes of the rollers, but are inclined thereto. Thisinclination is due to the fact that the cutting edges are screw-threads,as will be readily understood. The degree of inclination of coursevaries with the pitch of the threads.

The form' of the thread which I prefer to use has one side substantiallyperpendicular and the other side inclined, as shown in Fig. 2, makingwhat is known as a ratchetthread. A great variety of other threads,however, may be used where desirable.

The method of forming the threads in the rollers is immaterial, and thesame may be made in a number of ways, as by cutting, grinding, orrolling, either before or after hardening. The material of which therollers are made is also immaterial so long as they are hard enough todo the work required of them. With threads extending around the rollerswithout interruption the slits will be continnous-that is, each slitwill extend diagonally across the sheet to the side edge of the same. Ofcourse if the sheet is introduced at an angle to the axes of the rollersequal to the inclination of the slitting-threads the cuts will beparallel to the edges of the sheet, assuming the latter to berectangular in form. If one of the rollers, preferably both, be groovedlongitudinally, as in Fig. 3, so as to interrupt the threads, the slitsin the sheet of material will be in rows, as those shown in Fig. 5. Theparticular rollers illustrated in Fig. 3 each have eight equidistantgrooves, thus making.

eight rows of slits in a space equal to the circumference of theroller,as will be readily seen. The length of the slit is thereforeequal to onetenth of the circumference less the spaces at the ends ofthe slits, which spaces are each equal to the width of the grooves. Itis obvious that the number of rows in a given space depends upon thenumber of independent cutters, as a Z), into which the threads aredivided by the grooves.

By interrupting the cutting-threads alternately and in staggeredrelation, as shown, for example, in Fig. 4, the slits will becorrespondingly staggered. This effect is shown in Fig. 6. The length ofthe slits will of course depend upon the length of the independent out-One or both of the ting edges made by interrupting the threads.Bystopping out the threads in different ways a great variety of effectsmay beproduced.

The chief advantage of -my invention resides in its great accuracy. Asis well known, it is extremely difiicult, if not impossible, to cut orform on a cylinder a number of shearing edges of the kind heretoforeproposed (which are, in effect,merely a number of sheardisks placed sideby side) with such accuracy that the spaces between the same shall beexactly equal and the shearing edges themselves lie in exactly parallelplanes. If the rollers are not so constructed, the register of the edgeson one with those of the other is not exact, with the result that theoperation of the rollers is unsatisfactory, being imperfect andirregular. Screw-threads, on the other hand, may readily be cut with thegreatest accuracy, so that the shear edges of the two rollers will bealways in perfect register, giving a perfectly clean and regular out.The threads may also be sharpened with the same facility, whereas it isalmost impossible to sharpen circular cutters without distorting theedges thereof from the exact planes in which they should work.

Having now described my invention, what I claim is- 1. In a machine ofthe character described, in combination, a pair of rollers, one having aright-hand thread coacting with a left-hand thread on the other, as setforth.

2. In a machine of the character described, in combination, a pair ofslitting-rollers, one having a right-hand thread coacting in shearingengagement with a left-hand thread on the other, as set forth.

3. In a machine of the character described, in combination, a pair ofslitting-rollers, one having a right-hand thread coacting in shearin gengagement with a left-hand thread on the other, said threads beinginterrupted to form one or more series of cutters, as set forth.

4. In a machine of the character described, in combination, a pair ofslitting-rollers, one having a thread coacting in shearing engagementwith a thread of the opposite kind on the other, and having one or morelongitudinal grooves interrupting the thread to form one or more seriesof circumferential cutters, as set forth.

5. In a machine of the character described, in combination, a pair ofslitting-rollers, one

having a thread coacting in shearing engage-- ITO ment with a thread ofthe opposite kind on the other, each having one or more longitudinalgrooves interrupting the threads to form independent circumferentialcutters, as set forth.

6. In a machine of the character described, the combination of a pair ofrollers having opposite screw-threads in shearing engagement with eachother, and means for adjusting the degree of such shearing engagement,as set forth.

7. As a new article of manufacture, a slitthreads thereon formingcutting edges, and a ting-roller consisting of a cylinder having membercooperating with the said roller, as screw-threads thereon, said threadsbeing inset forth. terrupted to form independent circumfere'n- ALBERT F.MADDEN. 5 tial cutters, as set forth. W'itnesses:

In a machine of the character described, M. LAWSON DYER, the combinationof a roller having screw- S. S. DUNHAM.

